Note 12 - Fair Value Measurements (Details Textual) - USD ($)	Sep. 30, 2018	Mar. 31, 2018	Sep. 30, 2017
Impaired Financing Receivable, Recorded Investment, Total	$ 8,561,924	$ 8,720,339	$ 8,859,798
Real Estate Acquired Through Foreclosure	587,978	457,778
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Impaired Financing Receivable, Recorded Investment, Total	8,561,924	8,720,339
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	259,723	266,256
Real Estate Acquired Through Foreclosure	$ 587,978	$ 457,778

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
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-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5162-111524

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-Name Accounting Standards Codification
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